Wladimir Klitschko, the former world heavyweight boxing champion who retired Thursday, smiled when asked to recall his 1996 Atlanta Games experience, saying “the Olympics have changed my life.”

Before going 64-5 as a pro, Klitschko won super heavyweight gold at age 20 at Ukraine’s first Summer Olympics as an independent country. Friday is the 21st anniversary of the gold-medal bout.

“I have great memories,” Klitschko said in an interview two years ago at Madison Square Garden. “Meeting Muhammad Ali. … He was visiting the [athletes’] village, gathering a lot of people. I was one of them. It was exciting to see him in person. I didn’t get a chance to shake his hand.”

Klitschko said that was the first time he was close to Ali. The two Olympic champions met several more times before Ali died June 3, 2016.

Klitschko’s second memory of the Atlanta Games was of the Centennial Olympic Park bombing on July 27.

“One of the memories is the bombing of the disco, where my friends went to, and I was there before,” Klitschko said. “But I left, because I have to be in the schedule and sleep. When I heard the next morning, which was right on the other side of the campus where we were staying, it was really sad. Thankfully, nobody from my team got injured, but they were there.”

Klitschko auctioned his gold medal in 2012 for $1 million, all of which went to his and older brother Vitali Klitschko‘s charity. In a gracious gesture, the buyer reportedly immediately returned the medal back to the Klitschko family after the sale.

BERLIN (AP) — Former heavyweight world champion Wladimir Klitschko announced his immediate retirement from boxing on Thursday.

The 41-year-old Klitschko dominated the heavyweight scene for a decade but lost to Britain’s Anthony Joshua in April after a technical knockout in the 11th round. He had been expected to face Joshua in a rematch in November.

In a statement released by his management on Thursday, Klitschko said: “As an amateur and a professional boxer, I have achieved everything I dreamed of, and now I want to start my second career after sports.”

He said that he had deliberately taken a few weeks to reach a decision “to make sure I had enough distance from the (first Joshua) fight at Wembley Stadium.”

Klitschko was 64-5 in a career that began in 1996 after he won the Olympic gold in Atlanta.

The Ukrainian racked up notable wins over the likes of David Haye and Ruslan Chagaev, but lost his titles to British fighter Tyson Fury in 2015 and was unable to reclaim the WBA and IBF belts against Joshua.

Klitschko followed his older brother Vitali Klitschko into boxing. Both found immediate success in the professional ring, and held all of the main heavyweight titles between them when Vitali Klitschko retired in 2013.

They never fought each other, saying that would break a promise to their mother.

The Klitschko brothers’ hard-hitting style inside the ring and relaxed, multilingual approach outside it made them famous beyond boxing. Wladimir Klitschko even made a cameo appearance in a 2007 romantic comedy movie in the brothers’ adopted home of Germany.

He also followed his older brother into politics, addressing crowds alongside his fiancee, the U.S. actress Hayden Panettiere, during anti-government protests in Ukraine in 2013. Vitali Klitschko has since become mayor of the Ukrainian capital Kiev.

LONDON (AP) — Anthony Joshua wasn’t wrong when he raised his hands in victory after knocking Wladimir Klitschko down in the fifth round of what looked like a one-sided heavyweight title fight. He was just celebrating too early.

The rookie mistake allowed Klitschko to rally, nearly taking the lead as the two 6-foot-6 men went to the 11th round — four rounds longer than any Joshua fight had ever gone.

That’s when Joshua unleashed a brutal uppercut that spun Klitschko around, leading to a win that set off British celebrations in Wembley Stadium and beyond Saturday night and cemented the 27-year-old as boxing’s new superstar.

Rounds 5 and 6 featured some of the best heavyweight action since Mike Tyson, Evander Holyfield and Lennox Lewis — the latter two sitting ringside — ruled the division.

The two men in the ring were both Olympic super heavyweight champions. Joshua took gold for Great Britain in 2012, and Klitschko won for Ukraine in 1996.

Klitschko, who had barely thrown any power punches before the knockdown, came back to make the end of the fifth round interesting and knocked Joshua down in the next round.

With an entire country screaming for him, Joshua — who had knocked all his previous opponents out by the end of the seventh round — looked tired. But he saved his best for the late rounds, particularly the uppercut that will be a YouTube moment for decades.

Klitschko didn’t fall down after the uppercut, but Joshua was all over the stunned former champ and dropped him with a left hook. Klitschko got up only to take even more punishment. Joshua knocked Klitschko down again and was landing punches to his head on the ropes when referee David Fields moved in to stop the bout late in the 11th round.

“When you go to the trenches, that’s when you find out who you really are,” Joshua said. “In this small little ring here, there’s nowhere to hide.”

The biggest heavyweight title fight in more than a decade had a little something for everyone, and Joshua finished off in style.

“As I said from the get-go, it will be a boxing classic and the best man will win,” Joshua said.

Klitschko’s rally was inspiring, starting soon after he was knocked down in the fifth. By the end of the round, it was Klitschko pummeling a tired Joshua.

Joshua was still feeling the effect of those punches when he was dropped by a right hand in the sixth round. Klitschko began piling up rounds and it seemed like the savvy Ukrainian would quiet the hometown fans, until Joshua turned things around with that vicious right uppercut.

“If you don’t take part, you’re going to fail,” Joshua said. “Just give it a go and you never know the outcome.”

Joshua was up 96-93 and 95-93 on two scorecards, while Klitschko was ahead 95-93 on the third going into the final round. The Associated Press had it 94-94.

Klitschko, who reigned over the heavyweight division for a decade, was fighting both Joshua and Father Time at the age of 41. He looked to be overmatched in the early rounds, but fought his best after he was knocked down.

It was anyone’s fight when Joshua landed the uppercut that proved decisive, much to the delight of his countrymen who packed England’s national stadium for the highly anticipated bout.

“As I said I’m not perfect but I’m trying,” said Joshua, who was fighting for only the 19th time as a pro.

Joshua had never been beyond seven rounds, and it looked like he might be running out of gas as he tried to find his legs following the knockdown in the sixth. Klitschko, in his 29th world title fight, seemed to be taking the advantage in the later rounds, until the uppercut sent him spinning across the ring.

“It was really sad I didn’t make it tonight,” Klitschko said. “I was planning to do it. It didn’t work. But all respect to Anthony.”

Joshua defended his heavyweight titles and his undefeated record in a bout that lived up to its billing as the best matchup after a long drought in the heavyweight division. Already a hero in his native England, he may become one worldwide.

Joshua said before the bout that it was just two men in the ring, and nothing more than that. But it was clear by the crowd’s reaction as he came back to win that it was a lot more to many fans.

It was a battle of massive heavyweights, with both standing 6-foot-6. Joshua weighed 250.1 pounds to 240.5 for Klitschko.

Klitschko fell to 64-5 in a long career that began in 1996 after he won the Olympic gold in Atlanta. It may have been his last fight.